1. Field of the Invention
The present invention relates to image processing, and more particularly, to a method and apparatus for correcting an image under circumstances where degradation of an image, such as due to low light-intensity occurs.
2. Description of the Related Art
As the number of users using digital image devices including a digital camcorder and a camera phone are rapidly increasing nowadays, the functions of digital image devices are becoming more diverse. In particular, a rapidly increasing demand for security requires image processing techniques for devices such as closed-circuit televisions (CCTVs), which are fixed at a particular location and take images of that location.
In devices installed at a fixed position for taking images of the same place, such as security cameras or CCTVs, it is possible to obtain data of decent quality without degradation when taking images during the day-time because there is enough light. However, when the images are taken at night-time, problems occur in the image such as appearance of noise or a decrease in dynamic range, due to lack of light.
As described above, when conventionally storing an image while a device, for example a security camera, is fixed, a light-intensity may repetitively change between adequate and inadequate. If the light-intensity is inadequate when taking an image, a lot of noise may be generated or degradation such as a decrease in dynamic range of luminance values of the image may occur. At this time, if a new object comes into a camera screen, it is difficult to distinguish the object from the background because of the degradation of the image. It is also difficult to identify the object because of the noise and the decrease in dynamic range.